Using Once-Fired Military Brass
by Stuart A. Leach a.k.a. "the Colorado Gray Fox"

Every NRA Highpower shooter is tempted to use the
once-fired 30-06, 7.62/308 and 5.56/223 military
brass advertised in magazines and catalogs. The
price is usually low compared with virgin commercial
cases, and it somehow seems right to use GI brass in
a service rifle. There are a few things to know
about military brass before you start using it for
competition, and I'd like to offer a few hints and
tips.

Military brass is available from various sources,
and in various conditions. Dealers actually package
by weight, so the box or bag may be a few rounds
short or long. Cheapest will be standard NATO ball
cases, straight from the training ranges. It will be
dirty, some cases will be damaged, and may be from
mixed lots or several makers. It may have been fired
in rifles or machine guns. As price goes up, so does
quality- cleaner, sorted by headstamp, etc. The
highest grade is once fired GI match brass, which
will have been fired in rifles, and has no primer
crimp. GI 7.62/308 match is getting scarce as
military competitors switch to the M16.

Keep in mind that military 7.62/308 and 30-06 brass
contains more metal than commercial cases. GI 30
caliber cases weigh 7 to 10% more than civilian
brass; the extra metal is found in the rear third of
the case. This means less internal volume, and
powder charges need to be reduced to avoid excessive
pressure. There is little difference between
military and commercial 223Rem/5.56NATO brass.

Some dealers sell brass that has been "processed"-
tumble cleaned, de-primed, and the primer retaining
crimp removed. While this saves some work, I have
seen a batch of 5.56/223 where the primer pocket was
reamed too deeply, leaving the new primer
unsupported for half its depth. Better to do the
work yourself.

Assuming we have a batch of NATO ball cases, here
are the steps to get it ready for use:

Inspect the cases, and throw out any with serious
damage to mouth or rim. True up out-of-round case
mouths with a tapered punch, such as a nail set, so
they will enter the sizing die smoothly.

De-prime with a Lee or RCBS de-prime die. Then clean
well in tumbler or vibratory cleaner for several
hours. All the dirt and grit must be removed to
avoid damage to sizing dies.

If the cases were fired in a loose chambered rifle,
or a machine gun, a regular sizing die may not
reduce the base diameter enough to chamber in your
rifle. The thicker web and case walls spring back
more than civilian cases. We usually don't know what
sort of gun or guns the brass came from, so it's
best to return each case to minimum dimensions
before loading and firing the first time in your
rifle. Lube the cases well, inside and out, and size
in a special small base die. I share small base dies
with other shooters. Clean again to remove sizing
lube. Trim to length, then chamfer and deburr case
mouths.

Ream or swage out the primer crimp. Reaming cuts
away the crimp, using an inexpensive hand tool.
Reaming carelessly can result in an oversize or oval
pocket. Swaging moves metal out of the way, and
slightly work hardens the pocket area. Swaging tools
(RCBS is adequate, Dillon is superb) are more costly
and complex, but once adjusted do a better job than
reaming. Use a case mouth chamfer tool to put a
light chamfer on the pocket to ease entry of the new
primer.

For best results, use a flash hole reamer to remove
internal burrs. A primer pocket uniformer will also
help insure consistent ignition by making the
pockets of equal depth, and flat on the bottom.